<div class="input-prepend">
    <span class="add-on">用户名:</span>
    <input class="logintxt" type="text" size="20">
</div>
<div class="input-prepend">
    <span class="add-on">密码:</span>
    <input class="logintxt" type="password" size="20">
</div>
<div class="input-prepend">
    <span class="add-on">验证码:</span>
    <input class="logintxt" type="text" size="7">
    <img class="safecode" title="换一张" src="http://login.sina.com.cn/cgi/pin.php?r=20005262&s=0&p=0e3d5b9828d7d564dfbb48471161bcfe511c" height="28">
</div>
<div class="input-prepend"><a href="#" target="_blank">注册新账户</a> <a href="#" target="_blank">忘记密码？</a></div>
<style type="text/css">
    .input-prepend{clear:both;padding:7px 25px;height:18px;color: #333333;font-family: "Helvetica Neue",Helvetica,Arial,sans-serif;font-size: 12px;line-height: 18px;}
    .add-on{width: 4em;text-align: right;display: block;float: left;border-radius: 2px 0 0 2px;margin-right: -1px;background-color: #fafafa;border: 1px solid #CCCCCC;font-weight: normal;height: 18px;line-height: 18px;min-width: 16px;padding: 4px 5px;text-shadow: 0 1px 0 #FFFFFF;vertical-align: middle;}
    .logintxt{float: left;border-radius: 0 2px 2px 0;margin-left: 0;margin-bottom: 0;-moz-transition: border 0.2s linear 0s, box-shadow 0.2s linear 0s;border: 1px solid #CCCCCC;font-size: 13px;height: 18px;line-height: 18px;padding: 4px;font-family: "Helvetica Neue",Helvetica,Arial,sans-serif;}
    .input-prepend a{line-height:28px;float: left;margin-left:10px;text-decoration: none;}
    input:focus{border-color: rgba(82, 168, 236, 0.8); box-shadow: 0px 1px 1px rgba(0, 0, 0, 0.075) inset, 0px 0px 8px rgba(82, 168, 236, 0.6); outline: 0px none;}
    .input-prepend .safecode{margin:0 0 0 8px;cursor: pointer;float: left;}
</style>